Various electro-optical systems have been developed for reading optical indicia, such as barcodes. A barcode is a coded pattern of graphical indicia comprised of a series of bars and spaces of varying widths, the bars and spaces having differing light reflecting characteristics. The pattern of the bars and spaces encode information. Barcode may be one dimensional (e.g., UPC barcode) or two dimensional (e.g., DataMatrix barcode). Systems that read, that is, image or scan and decode barcodes employing imaging camera systems or laser scanner systems are typically referred to as optical scanners or barcode scanners.
Optical scanners may be portable or stationary. A portable optical scanner is one that is adapted to be held in a user's hand and moved with respect to target indicia, such as a target barcode, to be read that is, imaged or scanned and decoded.